FIELD OF THE INVENTION
The invention is directed to a regulating and controlling device for a fluid pressure booster installation, in particular a high-pressure cleaning installation containing
a pressure generating unit with a pump which is driven by a motor, the working fluid whose pressure is to be increased being fed to the suction connection of the pump, and the pressure connection of the pump is connected with a check valve whose outlet side is connected to the pressure outlet of the installation from which the working fluid can be removed at high pressure, PA0 a relief valve which can be adjusted with respect to pressure as appropriate for operation, the input of the relief valve being connected with the pressure connection, its output being connected with the suction connection, and its control input being connected with the outlet side of the check valve, PA0 and a pressure switch with a large ON-OFF switching differential which connects the motor to the mains and contains a first cylinder-piston arrangement which is connected with the outlet side of the check valve and whose piston rod can contact an intermediate member which is movably supported in the switch frame and pretensioned in the direction of a first limit position by means of a first spring and coupled with a movable contact carrier via a snap-in or locking arrangement, PA0 wherein the intermediate member moves the contact carrier from its ON position into an OFF position in a movement which proceeds from the first limit position occupied by the cylinder-piston arrangement in the absence of pressure and is directed toward the second limit position, and wherein the intermediate member moves the contact carrier into the ON position before reaching the first limit position at a first lower pressure with a reverse movement which is effected by the drive of the first spring against the oppositely directed force of the cylinder-piston arrangement, PA0 and wherein the intermediate member, proceeding from a position predetermined by the first cylinder-piston arrangement, can be moved farther in the direction of its second limit position by an external force simply by overcoming the sum of the spring forces of the first spring and locking arrangement. PA0 a third cylinder-piston arrangement having a stationary third cylinder, whose pressure connection is connected with the pressure connection of the pressure generating unit, whose piston-piston rod unit which is pretensioned by a third spring against an inner stop defining the moved in state is lifted from the inner stop when the pressure connection is acted upon by a third lower pressure and comes to rest at an outer stop at a slightly greater third upper pressure, wherein the third upper pressure is greater than the first lower pressure (switch-on pressure) and less than the second upper pressure, PA0 a gear unit arrangement which is driven by the second piston-piston rod unit and by the third piston-piston rod unit and has a trigger element which can engage at the intermediate member of the pressure switch, PA0 wherein the trigger element can be moved from an inactive limit position situated outside of the movement path of the intermediate member into an active limit position in which it acts on the intermediate member with a pressing surface so as to move the intermediate member toward its second limit position with a force sufficient to overcome the spring forces acting on the member, and PA0 wherein the gear unit arrangement moves the trigger element into its active limit position exclusively when the second piston-piston rod unit contacts its outer stop and the third piston-piston rod unit contacts its inner stop.